During manufacture of semiconductor chips, the semiconductor chips are subjected to reliability testing. A semiconductor chip that fails the reliability testing can be weeded out, thus preventing early failures during lifetime of the semiconductor chip.
Burn-in is an example of a reliability testing technique. During the burn-in, the semiconductor chips on a burn-in board are placed in an oven and exposed to temperatures higher than operating temperatures of the semiconductor chips. The semiconductor chips that fail to function in higher temperatures for a certain burn-in time can be detected as faulty. However, the oven is bulky and area inefficient. The oven is also expensive resulting in an increase in manufacturing cost of the semiconductor chip. High speed testing in the burn-in is further difficult to achieve due to limited clock rates resulting from high number of the semiconductor chips on the burn-in board. External sources are also required to heat the oven, the burn-in board, and the semiconductor chip which in turn leads to heating times longer than that required by the semiconductor chip in isolation, since the semiconductor chip has a lower thermal mass in isolation than that when the external sources are used. Moreover, time taken to heat up and to cool down the semiconductor chip during the burn-in is a sizeable fraction of total time for the burn-in. For example, the time required to heat up and to cool down the semiconductor chip is about 2 hours in a total time of 8 hours for the burn-in, making the burn-in time consuming.